1. Field of the Invention
The present invention relates to networking systems, and, more particularly, to wireless networking systems.
2. Description of the Related Art
A modern car has complex functionality and a network architecture that supports numerous functions. It has been projected that the electronics inside a car will increase from about twenty-five percent of the car's total cost currently to about forty percent of the car's total cost in the foreseeable future. The increase of electronics in a car will place demands of better and more sophisticated network structures. The degree of networked infrastructure in a car as well as the sophistication of the network is specific to the car manufacturer, make and model. While generalizations about the networking infrastructure of a car do not hold true, a high-end car usually has more than one wired network. Typically, a high-end car has a high bandwidth network for power-train, and a relatively lower bandwidth network for body control and comfort features at a minimum. Lower-end cars tend to have fewer networked features. Costs associated with networking a car are the costs of development and testing of a network architecture, layout and planning. Due to the high degree of reliability expected from automobiles and the associated design cost, manufacturers are extremely prudent in adding new features or altering the existing network architecture.
Vehicles are known to be provided with steering wheel pushbuttons which may be wired to selected components of the automobile, for example, to a body controller area network (CAN) and to a gearbox. This wiring may enable the user to control radio functions and comfort functions manually from the steering wheel. Additionally, some functions inherently require communications with multiple control units and subnetworks. For example, a direct gear shift change control pushbutton may communicate with a gearbox electronic control unit (ECU), body control module, motor ECU, damping ECU, and steering column control unit.
The known wired architectures are very constraining in the variety of functional controls that can be provided. Further, the automotive manufacturers make decisions regarding what functions to provide to the driver at the steering wheel. While lower-end cars have a very limited networked architecture, higher-end cars may have up to three CAN networks with numerous sub networks like LIN (Local Interconnect Network). The rigidity of the known network architecture and the architecture's associated lack of flexibility therefore allow only limited functions to be controlled from the steering wheel.
In recent years, wireless networks have received much attention in research and development from industry and academia. While the cost of radio frequency integrated circuits has been on the decline, the technology itself has attained a level of maturity. Currently, it is possible to build much lower cost wireless nodes that may be embedded in any environment, which was not possible just a few years ago. Such wireless networks are therefore candidates for inclusion in future cars. One of the main advantages that in-vehicle wireless networks offer over their wired counterparts is the ease and flexibility with which they can be deployed. Due to the absence of wire placement requirements, wireless networks and wireless devices can also be made to reach inaccessible areas, or components inside rotating parts or chambers. In the absence of wires and connectors for wires, enhanced reliability can be achieved, particularly in applications where wiring is drawn to parts that undergo mechanical movement. Further, these wireless networks may also be easier to repair.
As is currently known, certain aspects of car functionality such as remote keyless entry, tire pressure monitoring, remote starting and immobilizing, etc. may depend on wireless technology. However, these wireless applications may be considered unreliable in the sense that their current implementations offer no reliability guarantees. Further, the wireless applications are not networked, but rather are isolated from other systems. Having no requirement for wiring, in-vehicle wireless networks have a much greater potential to serve a variety of functions.
What is neither disclosed nor suggested by the prior art is an arrangement for a wireless network in which wireless nodes may be attached to moving parts of a vehicle or other machine.